1. Field of the Invention
This disclosure relates to fasteners for connecting objects to bodies, and more particularly to an embedded receiver for fasteners.
2. Discussion of the Prior Art
Fasteners come in many shapes and sizes. Most fasteners generally serve to connect two or more objects. Nails, which is a common name for small spikes, and other spike-type fasteners, have been around for centuries. Unlike receivers for threaded fasteners, such as wing nuts, speed nuts, T-nuts, hex nuts, etc., spike-type fasteners do not have equivalent individual receivers. Instead, the receiver function for a spike-type fastener generally is provided by the material into which the fastener is driven. For example, most commonly nails are received by timbers.
Machines to make “cut” nails produced “square nails”, as their cross-section was square, or nearly so, due to the stock from which these nails were cut. Square nails later gave way to tapered nails. Still later, machines provided for increased production, lower cost, greater standardization, and wide spread adoption of manufacturing of nails. In turn, cutting machines gave way to processing wire of a uniform thickness into “wire nails”, having a cylindrical shaft, which again lowered costs.
Within the rail industry, spikes with chisel tips have been used in securing rails to crossties, which are sometimes called “sleepers”. Such spikes also are called “cut spikes” to differentiate them from spikes with threads. Cut spikes also are called “crampons”, which more commonly are used in rock climbing. Rail spikes are essentially large nails with flat, or tapered sides, an oversized, offset head and a chisel-shaped, flat-edged tip.
Modern threaded fasteners are based on a design principle that was first thought to be used as a conveyor that moved material internal to a twisted thread as it was rotated. Standardized systems of screw threads, as well as nuts, have been developed. There are two general types of threaded fasteners, namely, the screw and the bolt. The screw generally is a single piece with two distinct sections, a head and a shaft. The shaft may be fully, or partially threaded. For general purpose screws, the end of the thread typically is pointed and the threaded shaft is either straight, slightly tapered or a combination of the two. Some screws that are tapered are self-tapping, or otherwise referred to as self-threading.
There are many configurations for screw heads, such as Bugle, Countersunk, Button, Fillister, Flat Head, Oval (sometimes called raised head), Pan, Round, or Truss Head. There also are many configurations by which to drive or force rotation of screws, such as Hex, Hex Socket (also called Allen head), One-Way Security, Phillips Head, Robertson (also called square drive or square socket head), Spline Drive, Straight Slotted, Torx Drive, or Security Torx. Quite simply, when a screw is rotated in one direction, the threads move the screw deeper into the material to which it is being fastened, and if rotated in the opposite direction the screw backs out of the material.
By comparison, a bolt has a head and a threaded rod or shaft, but essentially has no taper to the shaft, and a flat end. Rotating the head, rotates the threaded shaft which moves the shaft through a specific matching receiver, which often is called a “nut”. The free space between the head of a bolt and the face of the matching nut is reduced as the threaded shaft or the nut is tightened, thereby providing a clamping load. Sometimes the head and threaded shaft remain in place while the nut is tightened, or the nut may be held in place while the bolt head and accompanying shaft are rotated. There are many configurations for bolt heads including, for example, Hex, Rounded, and Slotted.
The major difference between screws and bolts are the minimum number of parts necessary to provide secure connection. For a screw, generally only one part is necessary as the material receiving the screw provides the resistance to extraction, as the screw threads bear on the material. For a bolt, two parts are necessary, the bolt and the receiver, the latter being most commonly in the form of a hexagonal-shaped nut. Some fasteners are referred to as a screw, but are configured for use with a receiver, and are more properly a form of bolt. For instance, Machine Screws are twisted into a receiver such as a nut, the end of the screw is generally flat, and the shaft is not tapered.
The term “receiver” is being used herein with respect to the prior art as a generic name for a second part of a fastener. For threaded fasteners, the receiver generally is free to move, in the sense that the receiver is not attached to anything else. Receivers that are referred to as a nut can be in various configurations, such as a Cap, Hex, Square, or Wing Nut. There also may be a captive nut, such as a T-Nut, which is embedded at the surface of an object and typically includes an elongated, threaded cylinder that reaches through a portion of the object.
With few exceptions spikes are generally received by the material into which they are driven and do not have a separate receiver component. Most commonly, spikes and nails are received by wood. Only the material receiving a spike-type fastener provides resistance to lateral motion and extraction. This is a problem well known to anyone who has hung a very heavy picture on a simple nail that was driven into gypsum-based wallboard. The nail will tend to crush the material downward as an excessive load is applied to the shaft, near the head of the nail. This can result in an enlarged hole in the wallboard, significantly compromising the resistance to extraction of the fastener.
Forces acting on prior art spike-type fasteners, whether in the longitudinal direction of extraction or within a plane perpendicular thereto, can act to loosen such fasteners, rendering them less effective. The present disclosure seeks to overcome disadvantages within the prior art to provide more affective fastener retention and without requiring a specific location for the fastener.